Severe Weather in the U.S. under a Changing Climate
Dr. Donald J. Wuebbles, The Harry E. Preble Professor of Atmospheric Sciences
School of Earth, Society, and Environment
Department of Atmospheric Sciences
University of Illinois
The U.S. National Climate Assessment (NCA) draws upon the latest scientific understanding of climate and climate change, synthesizing recent advances in the understanding of the science of climate change, and providing a succinct overview of the past and projected effects of climate change on the United States.
This presentation will provide an overview of draft findings from the 2013 NCA report chapter on the science of climate change, including observed trends and projected future climate changes for the United States. One of the major findings is that there has been an increase in some key types of extreme weather events, especially in heat waves and large precipitation events, in the U.S. (and throughout the world) over the last 50 years. There has been an increase in the number of historically top 1% of heavy precipitation events across the U.S. The pattern of precipitation change in general is one of increases generally at higher northern latitudes (because as the atmosphere warms it holds more moisture) and drying in the tropics and subtropics over land.
Scientific analyses are also indicating a strong link between changing trends in severe weather events and the changing climate. Every weather event that happens nowadays takes place in the context of the changes in the background climate system. Every event is influenced by many factors. Human-induced climate change is now a factor in all weather events. This presentation provides a discussion of the current understanding of climate change in the U.S. and severe weather in particular.